Hi Guys,
I am developing a workflow for the business user, Please Observe below screenshot

Here A, B & C are the data connections, User wants a report that he will select columns in the data connections, according to his selection, he needs the output to be delivered.
Example: If he selects, A & B connection, then A&B join output should be activated/generated
If he selects, B & C connection, then B&C join output should be activated/generated
If he selects, A & C connection, then A&C join output should be activated/generated
Thanks in advance for the reply, much appreciated...